CHAPTER 6
CONCLUSION AND SUGGESTION
6.1. Conclusion
After doing all development for break schedule and work pattern by creating
program in Microsoft Excel, the conclusion of this research are drawn:
a. The algorithm generated to build new break schedule is explained in
Algorithm 1.
b. The criteria for selecting the best break schedule among several scenarios
are:
1) Working hour should not be more than five consecutive hours and
followed by rest period that should not be less than one hour (Thailand’s
Ministry of Labour, 1998).
2) The greatest value of maximum line can be handled by one stagger
among other scenarios with same total break time.
3) The least number of stagger team needed among other scenarios with
same total break time.
4) Total working hour for stagger that assigned in maximum capacity of line
teams can be handled is at least 8 hours.
5) Break time frame must be on multiplication of quarter hour.
6) Check all break duration for stagger team whether has same length or
not.
[image:1.595.88.516.160.739.2]c. The best break schedule achieved in this research can be seen in Figure 6.1.
58
d. The best break schedule achieved in this research assigns one stagger team
to handle 6 line teams.
e. The algorithm generated to build work pattern is explained in Algorithm 2.
f. The criteria for selecting the best work pattern among several scenarios are:
1) Workweek should not be more than 60 hours (EICC, 2014; Apple, 2013).
2) There must be two crews assigned on one day as there are three crews
in the company and two shift works in one day.
g. The best work pattern that has followed the regulation from EICC (2014) and
Apple (2013) can be seen in Figure 6.2.
Week MON TUE WED THU FRI SAT SUN
1 Work Work Work Work OFF OFF Work
2 Work Work Work OFF OFF Work Work
3 Work Work OFF OFF Work Work Work
4 Work OFF OFF Work Work Work Work
5 OFF OFF Work Work Work Work OFF
6 OFF Work Work Work Work OFF OFF
Work Work Work Work OFF OFF
Workweek (hours) 42
[image:2.595.87.517.76.711.2]Work Pattern
Figure 6.2. Work Pattern’s Final Result
h. As the same work pattern is applied for all crews, combination of assignment
for all crews regarding with shift work named shift schedule is generated.
The best result of shift schedule can be seen in Figure 6.3.
Mon Tue Wed Thu Fri Sat Sun Mon Tue Wed Thu Fri Sat Sun Mon Tue Wed Thu Fri Sat Sun
Day A A A A C C C C B B B B A A A A C C C C B
Night C C B B B B A A A A C C C C B B B B A A A
Off B B C C A A B B C C A A B B C C A A B B C
Mon Tue Wed Thu Fri Sat Sun Mon Tue Wed Thu Fri Sat Sun Mon Tue Wed Thu Fri Sat Sun
Day B B B A A A A C C C C B B B B A A A A C C
Night A C C C C B B B B A A A A C C C C B B B B
Off C A A B B C C A A B B C C A A B B C C A A
Figure 6.3. Shift Schedule’s Final Result
6.2. Suggestion
Several considerations for future research extension are level of production in the
company, cost incurred, and number of headcount. Level of production in the
can be created based on level of production. If there is a change for the
schedule, current schedule and proposed schedule can be compared considering
the cost incurred and number of headcount. The program also needs to be
developed for analysis as this research analyzes the schedule manually. By
60 REFERENCES
Alfares, Hesham K. (2001). Efficient Optimization of Cyclic Labor Days-Off
Scheduling. OR-Spektrum, 23 (2), 283-194.
Alfares, Hesham K. (2002). Optimum Workforce Scheduling Under The (14, 21)
Days-Off Timetable. Journal of Applied Mathematics & Decision Sciences,
6 (3), 191-199.
Alfares, Hesham K. (2006). Compressed Workweek Scheduling with Days-Off
Consecutivity Weekend-Off Frequency, and Work Stretch Constraints.
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Apple. (2013). Apple Supplier of Conduct. Accessed on March 3rd, 2014 from
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_Conduct.pdf.
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and Start-Time Flexibility in Continuous Tour Scheduling. Management
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(44), 12-14, 76.
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docs/EICCCodeofConduct5_English.pdf.
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Break-Time Constraint. Proceedings of the Asia Pacific Industrial
62 APPENDIX 1
USER GUIDE FOR BREAK SCHEDULE PROGRAM
Overview
This program is used for building break schedule automatically. However, this
program works as calculator only as the program cannot choose the best break
schedule over several scenarios created. In the input section, this program will
generate several scenarios based on possible values of break schedule
components. The output of this program is break schedule for all scenarios
generated in input section. This program is built on one of feature in Microsoft
Excel, VB Program.
Operating Break Schedule Program
1. Open Microsoft Excel’s file named Final Project DONE.xlsm
2. Make sure to enable Macro feature
3. Choose worksheet named Input
4. Look at break schedule section in Input sheet
5. Click command button named Input below break schedule’s input data
6. Fill in shift length in hour, number of line assigned, and break time in
minutes on user form showed
7. If there is mistype, click button named Clear to clean out data inputted in
user form
8. If cancelling to fill in break schedule’s input, click button named Cancel
and user form will be closed
9. If button named OK is clicked after fill in all input, several scenarios will be
generated automatically based on possible values from input data
10. After all scenarios are generated, click command button named RUN
Break Schedule and break schedule over all scenarios will be built in
worksheet named Break Schedule. If the value in break schedule is
greater than 5 hours or 300 minutes, it will be displayed by red colored
number. Break schedule that has red colored number cannot be
considered as good break schedule. If there are some break schedule
Editing Break Schedule Program
1. Open Microsoft Excel’s file named Final Project DONE.xlsm
2. Click on Developer tab. If there is no Developer tab, click File, select
Options, choose Customize Ribbon, Give check mark for Developer on
Main Tabs, and Click OK.
3. On Developer tab, click Visual Basic
4. Double click in Sheet1 (Input). In this sheet, there are several private sub
there.
5. Look at Private Sub Command_input_Click(). This private sub is used for
giving instruction when command button named Input for break schedule
is clicked.
3. Double click on UserForm_BreakSchedule. This forms display how user
form for break schedule would like to showed including instruction for
command button in user form.
4. Double click on user form. There are several private subs regarding with
the display on user form. Private Sub UserForm_initialize() is used for
displaying no values showed on textboxfor all input. Private Sub
Command_ok_Click(), it is used for generate the input on scenarios after
clicking command button named OK. The value on Work1_cont
represents initial first work. Currently value of Work1_cont is 15 with
increment 15. The value of Work1_cont will be tried by do loop command
until equal to 120. If there is change on value of Work1_cont, three parts
regarding with Work1_cont can be changed manually. The value for first
stagger break also can be changed manually. Currently minimum value
for b1 or break1 is 40 with increment 5 to find possible value for
combination of break. Those two values can be changed depend on the
needs. Private Sub Command_clear_Click() is used for clean out any
values in input after command button named Clear is clicked. Private Sub
Command_cancel_Click() is used for closing user form as canceling input
data in user form after command button named Cancel is clicked.
1. Double click on Sheet1 (Input). Look at Private Sub
RUNBreakSchedule_Click(). That is used for generate break schedule
based on scenarios created in Input sheets after clicking command button
64
2. Double click on Modules folder. There are two modules for break
schedule. Those are BreakScheduleScn1 and BreakScheduleScnOther.
Both modules there work as function to calculate break schedule that are
called in when command button named RUN Break Schedule is clicked.
BreakScheduleScn1 Module is used for calculating break schedule for
scenario 1 only. constraint_10AM is used for giving limitation when line
team gets long break. Currently, the value for constraint_10AM is 3. If 3
hours is too long to be the limitation, value for constraint_10AM can be
changed manually. BreakScheduleScnOther Module is used for
calculating break schedule for all scenarios generated in input except
APPENDIX 2
USER GUIDE FOR WORK PATTERN PROGRAM
Overview
This program is used for building work pattern automatically. However, this
program works as calculator only as the program cannot choose the best work
pattern over several scenarios created. In the input section, this program will
generate several scenarios based on possible values of placement of first day
work on work cycle. The output of this program is work pattern for all scenarios
generated in input section. This program is built on one of feature in Microsoft
Excel, VB Program.
Operating Work Pattern Program
1. Open Microsoft Excel’s file named Final Project DONE.xlsm
2. Make sure to enable Macro feature
3. Choose worksheet named Input
4. Look at work pattern section in Input sheet
5. Click command button named Input below work pattern’s input data
6. Fill in shift length in hour, break time in minutes, day-off in day, and work
cycle in day
7. If there is mistype, click button named Clear to clean out data inputted in
user form
8. If cancelling to fill in work pattern’s input, click button named Cancel and
user form will be closed
9. If button named OK is clicked after fill in all input, several scenarios will be
generated automatically based on possible values from input data
10. After all scenarios are generated, click command button named RUN
Work Pattern and work pattern over all scenarios will be built in worksheet
named Work Pattern. If the value of workweek is greater than 60 hours, it
will be displayed by red colored number. Work pattern that has red
colored number cannot be considered as good work pattern. If there are
some work pattern that pass the regulation, those will be evaluated later
66 Editing Work Pattern Program
1. Open Microsoft Excel’s file named Final Project DONE.xlsm
2. Click on Developer tab. If there is no Developer tab, click File, select
Options, choose Customize Ribbon, Give check mark for Developer on
Main Tabs, and Click OK.
3. On Developer tab, click Visual Basic
4. Double click in Sheet1 (Input). In this sheet, there are several private sub
there.
5. Look at Private Sub Input1_Click(). This private sub is used for giving
instruction when command button named Input is clicked.
6. Double click on UserForm_WorkPattern. This forms display how user form
for work pattern would like to showed including instruction for command
button in user form.
7. Double click on user form. There are several private subs regarding with
the display on user form. Private Sub UserForm_initialize() is used for
displaying no values showed on textboxfor all input. Private Sub
Command_ok_Click(), it is used for generate the input on scenarios after
clicking command button named OK. Private Sub Command_clear_Click()
is used for clean out any values in input after command button named
Clear is clicked. Private Sub Command_cancel_Click() is used for closing
user form as canceling input data in user form after command button
named Cancel is clicked.
8. Double click on Sheet1 (Input). Look at Private Sub
RUNWorkPattern_Click(). That is used for generate work pattern based
on scenarios created in Input sheets after clicking command button
named RUN Work Pattern.
9. Double click on Modules folder. Double click on WorkPattern Module. The
module works as function to generate work pattern that is called in when
command button named RUN Work Pattern is clicked. Currently, this
program generates work pattern only for 6 days and 7 days’ work cycle. If
there is any option of work cycle beside those values, the assignment for
work and day off on each week and each crew must be added manually.
